TESTING/LIN/cgbt02.f(3)

NAME
TESTING/LIN/cgbt02.f

SYNOPSIS

  Functions/Subroutines
subroutine cgbt02 (trans, m, n, kl, ku, nrhs, a, lda, x, ldx, b, ldb, rwork, resid)
CGBT02

Function/Subroutine Documentation

  subroutine cgbt02 (character trans, integer m, integer n, integer kl, integer ku, integer nrhs, complex, dimension( lda, * ) a, integer lda, complex, dimension( ldx, * ) x, integer ldx, complex, dimension( ldb, * ) b, integer ldb, real, dimension( * ) rwork, real resid)

CGBT02

Purpose:

    !>
    !> CGBT02 computes the residual for a solution of a banded system of
    !> equations op(A)*X = B:
    !>    RESID = norm(B - op(A)*X) / ( norm(op(A)) * norm(X) * EPS ),
    !> where op(A) = A, A**T, or A**H, depending on TRANS, and EPS is the
    !> machine epsilon.
    !>

Parameters
    TRANS

    !>          TRANS is CHARACTER*1
    !>          Specifies the form of the system of equations:
    !>          = 'N':  A    * X = B  (No transpose)
    !>          = 'T':  A**T * X = B  (Transpose)
    !>          = 'C':  A**H * X = B  (Conjugate transpose)
    !>

    M

    !>          M is INTEGER
    !>          The number of rows of the matrix A.  M >= 0.
    !>

    N

    !>          N is INTEGER
    !>          The number of columns of the matrix A.  N >= 0.
    !>

    KL

    !>          KL is INTEGER
    !>          The number of subdiagonals within the band of A.  KL >= 0.
    !>

    KU

    !>          KU is INTEGER
    !>          The number of superdiagonals within the band of A.  KU >= 0.
    !>

    NRHS

    !>          NRHS is INTEGER
    !>          The number of columns of B.  NRHS >= 0.
    !>

    A

    !>          A is COMPLEX array, dimension (LDA,N)
    !>          The original matrix A in band storage, stored in rows 1 to
    !>          KL+KU+1.
    !>

    LDA

    !>          LDA is INTEGER
    !>          The leading dimension of the array A.  LDA >= max(1,KL+KU+1).
    !>

    X

    !>          X is COMPLEX array, dimension (LDX,NRHS)
    !>          The computed solution vectors for the system of linear
    !>          equations.
    !>

    LDX

    !>          LDX is INTEGER
    !>          The leading dimension of the array X.  If TRANS = 'N',
    !>          LDX >= max(1,N); if TRANS = 'T' or 'C', LDX >= max(1,M).
    !>

    B

    !>          B is COMPLEX array, dimension (LDB,NRHS)
    !>          On entry, the right hand side vectors for the system of
    !>          linear equations.
    !>          On exit, B is overwritten with the difference B - A*X.
    !>

    LDB

    !>          LDB is INTEGER
    !>          The leading dimension of the array B.  IF TRANS = 'N',
    !>          LDB >= max(1,M); if TRANS = 'T' or 'C', LDB >= max(1,N).
    !>

    RWORK

    !>          RWORK is REAL array, dimension (MAX(1,LRWORK)),
    !>          where LRWORK >= M when TRANS = 'T' or 'C'; otherwise, RWORK
    !>          is not referenced.
    !>

    RESID

    !>          RESID is REAL
    !>          The maximum over the number of right hand sides of
    !>          norm(B - op(A)*X) / ( norm(op(A)) * norm(X) * EPS ).
    !>

Author
    Univ. of Tennessee

    Univ. of California Berkeley

    Univ. of Colorado Denver

    NAG Ltd.

Definition at line 146 of file cgbt02.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.